In:
Journal of Clinical Oncology, American Society of Clinical Oncology (ASCO), Vol. 33, No. 29_suppl ( 2015-10-10), p. 3-3
Abstract:
3 Background: Oral mucositis and skin dermatitis induced by oncological therapies can impair patients’ functional capacity and quality of life. Laser therapy has been proposed as an effective treatment for both conditions, although with an unclear mechanism. Laser irradiation seems to enhance mitotic activity of epithelial cells, fibroblasts and collagen fibres, but are we sure that it does not stimulate neoplastic cells as well? Two different mice models have been ad hoc created to investigate whether laser therapy can be safely performed even on neoplastic areas. Methods: First model: 4-NQO chemical carcinogen was administered to 50 mice for 16 weeks. During the 17 th week, 25 mice were subdued to 4 daily laser therapy sessions (970nm, 2.5W/cm2, duty cycle 50%, 2Hz, 180J/cm2), while 25 mice were used as controls. Afterwards, animals were sacrificed to perform histological analysis. Second model: Melanoma cells were implanted in 48 mice at the dorsal subcutaneous level. A tumour mass developed at the site of injection and mice were homogeneously divided into 4 groups according to tumour size: 3 groups were subject to different laser protocols (660nm, 100mW/cm2, CW, 3J/cm2; 800nm, 1W/cm2, CW, 20J/cm2 and 970nm, 60mW/cm2, CW, 6J/cm2) for 4 consecutive days, while the fourth group was used as control. All animals were euthanized to measure tumour volume and weight, and to quantify tumour invasiveness through immunohistochemistry (CD68 and Melan-A). Results: First model: the number/extension of dysplastic/neoplastic areas did not increased after laser irradiation (p 〈 0.05). Unexpectedly, while carcinomas are normally surrounded by dysplastic tissue displaying different degrees of cells alterations, laser treated carcinomas appeared as insulated lesions surrounded by healthy epithelium. Second model: tumour growth and weight and neoplastic cells infiltration were lower in all laser groups compared to the controls (p 〈 0.05). Conclusions: The above-presented results may also prove that laser therapy can be safely performed to treat oral mucositis and skin dermatitis even in patients with active oncological disease. A key-role of the immune system may explain the peculiar behaviour of carcinomas and melanomas in response to laser irradiation.
Type of Medium:
Online Resource
ISSN:
0732-183X
,
1527-7755
DOI:
10.1200/jco.2015.33.29_suppl.3
Language:
English
Publisher:
American Society of Clinical Oncology (ASCO)
Publication Date:
2015
detail.hit.zdb_id:
2005181-5
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